ABOUT THE SPEAKER
Luis von Ahn - Computer scientist
Luis von Ahn builds systems that combine humans and computers to solve large-scale problems that neither can solve alone.

Why you should listen

Louis von Ahn is an associate professor of Computer Science at Carnegie Mellon University, and he's at the forefront of the crowdsourcing craze. His work takes advantage of the evergrowing Web-connected population to acheive collaboration in unprecedented numbers. His projects aim to leverage the crowd for human good. His company reCAPTCHA, sold to Google in 2009, digitizes human knowledge (books), one word at a time. His new project is Duolingo, which aims to get 100 million people translating the Web in every major language.

More profile about the speaker
Luis von Ahn | Speaker | TED.com
TEDxCMU

Luis von Ahn: Massive-scale online collaboration

路易斯・范・安:大型在线共同创作

Filmed:
1,740,008 views

路易斯・范・安带来了新一代的验证码,通过真人回复来将扫描书籍电子化。他琢磨这种无数个在线合作还能为我们带来什么更大的益处。他在 TEDxCMU介绍了他的新项目,叫Duolingo。这个项目能帮助成千上万的人学习外语,同时又把网页内容进行快速准确地翻译,而这一切都是免费的。
- Computer scientist
Luis von Ahn builds systems that combine humans and computers to solve large-scale problems that neither can solve alone. Full bio

Double-click the English transcript below to play the video.

00:15
How many许多 of you had to fill out some sort分类 of web卷筒纸 form形成
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有多少人在填写网页表格时
00:17
where you've been asked to read a distorted扭曲 sequence序列 of characters人物 like this?
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需要识别像这样扭曲的词语?
00:19
How many许多 of you found发现 it really, really annoying恼人的?
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有多少人觉得很烦人?
00:21
Okay, outstanding优秀. So I invented发明 that.
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哇,不少呢。我就是发明这个的人。
00:24
(Laughter笑声)
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(笑声)
00:26
Or I was one of the people who did it.
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或者说我是其中之一
00:28
That thing is called a CAPTCHACAPTCHA.
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这个称作验证码
00:30
And the reason原因 it is there is to make sure you, the entity实体 filling填充 out the form形成,
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其理由是保证填写表格的是一个真人
00:32
are actually其实 a human人的 and not some sort分类 of computer电脑 program程序
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而不是什么电脑程序在操作
00:35
that was written书面 to submit提交 the form形成 millions百万 and millions百万 of times.
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可以不停地填写表格
00:37
The reason原因 it works作品 is because humans人类,
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这是因为人类
00:39
at least最小 non-visually-impaired非视觉受损 humans人类,
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至少是没有视力问题的人
00:41
have no trouble麻烦 reading these distorted扭曲 squiggly弯弯曲曲 characters人物,
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可以识别这些扭曲的文字
00:43
whereas computer电脑 programs程式 simply只是 can't do it as well yet然而.
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而机器做不到
00:46
So for example, in the case案件 of Ticketmaster特玛,
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比如说在票务大全网站上
00:48
the reason原因 you have to type类型 these distorted扭曲 characters人物
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你输入这些扭曲字符的原因
00:50
is to prevent避免 scalpers黄牛党 from writing写作 a program程序
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是防止黄牛写一个电脑程序
00:52
that can buy购买 millions百万 of tickets门票, two at a time.
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一次购买上万张票
00:54
CAPTCHAs验证码 are used all over the Internet互联网.
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验证码在网络上普遍应用
00:56
And since以来 they're used so often经常,
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因其普遍性
00:58
a lot of times the precise精确 sequence序列 of random随机 characters人物 that is shown显示 to the user用户
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很多时候使用者就会看到一些
01:00
is not so fortunate幸运.
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异常搭配的文字排序
01:02
So this is an example from the Yahoo雅虎 registration注册 page.
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这个例子来自雅虎注册网页
01:05
The random随机 characters人物 that happened发生 to be shown显示 to the user用户
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使用者看到的这几个随机字母
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were W, A, I, T, which哪一个, of course课程, spell拼写 a word.
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W,A,I, T,正好组成了“等”
01:10
But the best最好 part部分 is the message信息
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最有意思的是
01:13
that the Yahoo雅虎 help desk got about 20 minutes分钟 later后来.
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这是20分钟后的帮助页面
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Text文本: "Help! I've been waiting等候 for over 20 minutes分钟, and nothing happens发生."
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文字:“帮忙!我已经等了二十多分钟,没有任何变化。”
01:19
(Laughter笑声)
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(笑声)
01:23
This person thought they needed需要 to wait.
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这人以为网站让他等着
01:25
This of course课程, is not as bad as this poor较差的 person.
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当然还有更倒霉的
01:28
(Laughter笑声)
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(笑声)
01:30
CAPTCHACAPTCHA Project项目 is something that we did here at Carnegie卡内基 MelllonMelllon over 10 years年份 ago,
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验证码计划是我们十多年前在卡内基梅隆大学做起来的
01:33
and it's been used everywhere到处.
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并被广泛应用
01:35
Let me now tell you about a project项目 that we did a few少数 years年份 later后来,
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现在谈谈几年后我们做的一个项目
01:37
which哪一个 is sort分类 of the next下一个 evolution演化 of CAPTCHACAPTCHA.
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算是验证码的新生代版本
01:40
This is a project项目 that we call reCAPTCHA验证码,
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这个计划我们称之“reCAPTCHA”
01:42
which哪一个 is something that we started开始 here at Carnegie卡内基 Mellon梅隆,
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这个计划是从卡内基梅隆大学起步
01:44
then we turned转身 it into a startup启动 company公司.
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成为我们的启动公司
01:46
And then about a year and a half ago,
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一年半前
01:48
Google谷歌 actually其实 acquired后天 this company公司.
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谷歌收购了这个公司
01:50
So let me tell you what this project项目 started开始.
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现在我来说说这个项目的初始
01:52
So this project项目 started开始 from the following以下 realization实现:
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这个项目是出于以下认识:
01:55
It turns out that approximately 200 million百万 CAPTCHAs验证码
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每天全球范围内有大约2亿次
01:57
are typed类型 everyday每天 by people around the world世界.
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验证码输入
02:00
When I first heard听说 this, I was quite相当 proud骄傲 of myself.
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我头次听到的时候还挺自豪
02:02
I thought, look at the impact碰撞 that my research研究 has had.
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我想 我们的研究影响力不小啊
02:04
But then I started开始 feeling感觉 bad.
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接着我就感觉很难受
02:06
See here's这里的 the thing, each time you type类型 a CAPTCHACAPTCHA,
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因为每次你输入一个验证码
02:08
essentially实质上 you waste浪费 10 seconds of your time.
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你就浪费了10秒钟
02:11
And if you multiply that by 200 million百万,
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这个乘以2亿
02:13
you get that humanity人性 as a whole整个 is wasting浪费 about 500,000 hours小时 every一切 day
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全人类每天就浪费了50万个小时
02:16
typing打字 these annoying恼人的 CAPTCHAs验证码.
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来输入烦人的验证码
02:18
So then I started开始 feeling感觉 bad.
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我就很难受了
02:20
(Laughter笑声)
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(笑声)
02:22
And then I started开始 thinking思维, well, of course课程, we can't just get rid摆脱 of CAPTCHAs验证码,
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我开始思考 既然不能放弃验证码
02:25
because the security安全 of the Web卷筒纸 sort分类 of depends依靠 on them.
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因为网页安全依赖于此
02:27
But then I started开始 thinking思维, is there any way we can use this effort功夫
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那么有什么方法可以利用它
02:30
for something that is good for humanity人性?
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来做点好事呢?
02:32
So see, here's这里的 the thing.
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关键在于
02:34
While you're typing打字 a CAPTCHACAPTCHA, during those 10 seconds,
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当你在10秒钟内输入验证码的时候
02:36
your brain is doing something amazing惊人.
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你的大脑在做了不起的工作
02:38
Your brain is doing something that computers电脑 cannot不能 yet然而 do.
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这是电脑目前尚无法做到的
02:40
So can we get you to do useful有用 work for those 10 seconds?
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那么能不能让这10秒钟的工作变得有意义呢?
02:43
Another另一个 way of putting it is,
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也就是说
02:45
is there some humongous堆积如山 problem问题 that we cannot不能 yet然而 get computers电脑 to solve解决,
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有没有什么目前电脑无法解决的难题
02:47
yet然而 we can split分裂 into tiny 10-second chunks
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但是可以分割成10秒的单位小块
02:50
such这样 that each time somebody solves解决了 a CAPTCHACAPTCHA
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这样每个人通过验证码
02:52
they solve解决 a little bit of this problem问题?
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解决这个问题的一个小单位?
02:54
And the answer回答 to that is "yes," and this is what we're doing now.
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答案是肯定的话 这就是我们目前在做的
02:56
So what you may可能 not know is that nowadays如今 while you're typing打字 a CAPTCHACAPTCHA,
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也许你不知道 如今当你输入一个验证码
02:59
not only are you authenticating认证 yourself你自己 as a human人的,
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不仅仅是在证明你是真人
03:01
but in addition加成 you're actually其实 helping帮助 us to digitize数字化 books图书.
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也是在把书电子化
03:03
So let me explain说明 how this works作品.
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我来解释一下
03:05
So there's a lot of projects项目 out there trying to digitize数字化 books图书.
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目前有很多书籍电子化的项目
03:07
Google谷歌 has one. The Internet互联网 Archive档案 has one.
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谷歌有一个。 “互联网档案”有一个
03:10
Amazon亚马逊, now with the Kindle点燃, is trying to digitize数字化 books图书.
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现亚马逊的Kindle也有一个
03:12
Basically基本上 the way this works作品
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方法就是
03:14
is you start开始 with an old book.
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从一本旧书开始
03:16
You've seen看到 those things, right? Like a book?
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你见过书对吧?一本书?
03:18
(Laughter笑声)
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(笑声)
03:20
So you start开始 with a book, and then you scan扫描 it.
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首先扫描一本书
03:22
Now scanning扫描 a book
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扫描就是
03:24
is like taking服用 a digital数字 photograph照片 of every一切 page of the book.
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相当于把每一页照一张数码照片
03:26
It gives you an image图片 for every一切 page of the book.
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你就有了这本书每一页的照片
03:28
This is an image图片 with text文本 for every一切 page of the book.
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这是一本书每一页文字内容的照片
03:30
The next下一个 step in the process处理
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下一步就是
03:32
is that the computer电脑 needs需求 to be able能够 to decipher解码 all of the words in this image图片.
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电脑得解读这些照片上的每一个字
03:35
That's using运用 a technology技术 called OCROCR,
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这涉及到一个叫做OCR的技术
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for optical光纤 character字符 recognition承认,
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也就是光学字符识别
03:39
which哪一个 takes a picture图片 of text文本
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拍下一段文字的照片
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and tries尝试 to figure数字 out what text文本 is in there.
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然后识别出文字内容
03:43
Now the problem问题 is that OCROCR is not perfect完善.
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问题是光学字符识别的技术并不能解决所有问题
03:45
Especially特别 for older旧的 books图书
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特别对于旧书
03:47
where the ink墨水 has faded褪色 and the pages网页 have turned转身 yellow黄色,
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墨水褪色,书页泛黄
03:50
OCROCR cannot不能 recognize认识 a lot of the words.
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很多字OCR无法识别
03:52
For example, for things that were written书面 more than 50 years年份 ago,
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比如,五十多年前的书
03:54
the computer电脑 cannot不能 recognize认识 about 30 percent百分 of the words.
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有百分之三十的单词电脑无法识别
03:57
So what we're doing now
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我们做的就是
03:59
is we're taking服用 all of the words that the computer电脑 cannot不能 recognize认识
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摘录出电脑无法识别的单词
04:01
and we're getting得到 people to read them for us
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通过真人在网上输入验证码时
04:03
while they're typing打字 a CAPTCHACAPTCHA on the Internet互联网.
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阅读识别出来
04:05
So the next下一个 time you type类型 a CAPTCHACAPTCHA, these words that you're typing打字
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下次当你输入一个验证码时,你输入的那个单词
04:08
are actually其实 words that are coming未来 from books图书 that are being存在 digitized数字化
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实际是我们电子化书籍里
04:11
that the computer电脑 could not recognize认识.
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电脑无法识别的单词
04:13
And now the reason原因 we have two words nowadays如今 instead代替 of one
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现在我们使用两个而非一个单词的理由是
04:15
is because, you see, one of the words
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其中一个词是
04:17
is a word that the system系统 just got out of a book,
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系统把一个电脑无法识别的单词
04:19
it didn't know what it was, and it's going to present当下 it to you.
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提供给你
04:22
But since以来 it doesn't know the answer回答 for it, it cannot不能 grade年级 it for you.
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因为系统不认识这个单词 所以无法判断你的答案
04:25
So what we do is we give you another另一个 word,
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我们就加入另一个单词
04:27
one for which哪一个 the system系统 does know the answer回答.
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一个系统已经认识的单词
04:29
We don't tell you which哪一个 one's那些 which哪一个, and we say, please type类型 both.
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不告诉你哪个是已知的,哪个是未知的 请你将两者都输入
04:31
And if you type类型 the correct正确 word
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如果你能拼写正确
04:33
for the one for which哪一个 the system系统 already已经 knows知道 the answer回答,
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系统已认知的那个单词
04:35
it assumes假设 you are human人的,
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就判断你为真人
04:37
and it also gets得到 some confidence置信度 that you typed类型 the other word correctly正确地.
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这样对你输入的另一个单词就有所把握
04:39
And if we repeat重复 this process处理 to like 10 different不同 people
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我们把这个过程让十个人重复进行
04:42
and all of them agree同意 on what the new word is,
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如果他们对不识别单词的答案一致
04:44
then we get one more word digitized数字化 accurately准确.
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我们就得到了一个准确电子化的新单词
04:46
So this is how the system系统 works作品.
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这就是这个系统的工作原理
04:48
And basically基本上, since以来 we released发布 it about three or four years年份 ago,
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大约三四年前我们导入这个系统
04:51
a lot of websites网站 have started开始 switching交换
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许多网站已经从旧的验证码
04:53
from the old CAPTCHACAPTCHA where people wasted浪费 their time
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换成新的来帮助书籍电子化
04:55
to the new CAPTCHACAPTCHA where people are helping帮助 to digitize数字化 books图书.
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而不是浪费人们的时间
04:57
So for example, Ticketmaster特玛.
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比如“票务大全”
04:59
So every一切 time you buy购买 tickets门票 on Ticketmaster特玛, you help to digitize数字化 a book.
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每次你在它的网站上购票 就在帮助把书籍电子化
05:02
FacebookFacebook的: Every一切 time you add a friend朋友 or poke somebody,
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脸书:每次你加好友或者打招呼
05:04
you help to digitize数字化 a book.
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你就帮忙在把书籍电子化
05:06
Twitter推特 and about 350,000 other sites网站 are all using运用 reCAPTCHA验证码.
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推特和其他350,000个网站都在用reCAPTCHA
05:09
And in fact事实, the number of sites网站 that are using运用 reCAPTCHA验证码 is so high
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现在使用reCAPTCHA的网站是如此之多
05:11
that the number of words that we're digitizing数字化 per day is really, really large.
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每天我们电子化的单词数量惊人
05:14
It's about 100 million百万 a day,
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大概是每天一亿
05:16
which哪一个 is the equivalent当量 of about two and a half million百万 books图书 a year.
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这就是每年大概250万本书
05:20
And this is all being存在 doneDONE one word at a time
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而这一切仅仅都是通过人们在网上
05:22
by just people typing打字 CAPTCHAs验证码 on the Internet互联网.
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输入验证码来做到的
05:24
(Applause掌声)
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(掌声)
05:32
Now of course课程,
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当然
05:34
since以来 we're doing so many许多 words per day,
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因为每天处理的词是如此之多
05:36
funny滑稽 things can happen发生.
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难免有搞笑的状况
05:38
And this is especially特别 true真正 because now we're giving people
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特别是现在我们给出的单词是
05:40
two randomly随机 chosen选择 English英语 words next下一个 to each other.
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两个随机组合的英语单词
05:42
So funny滑稽 things can happen发生.
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就出现了有意思的事
05:44
For example, we presented呈现 this word.
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比如 我们给出了这个词
05:46
It's the word "Christians基督徒"; there's nothing wrong错误 with it.
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“基督徒” 这没什么问题
05:48
But if you present当下 it along沿 with another另一个 randomly随机 chosen选择 word,
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问题是另外一个随机抽取的词
05:51
bad things can happen发生.
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就把事情搞糟了
05:53
So we get this. (Text文本: bad christians基督徒)
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比如这个 (恶基督徒)
05:55
But it's even worse更差, because the particular特定 website网站 where we showed显示 this
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更糟的是 出现这个的网站
05:58
actually其实 happened发生 to be called The Embassy大使馆 of the Kingdom王国 of God.
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正好是“神之国度大使馆”
06:01
(Laughter笑声)
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(笑声)
06:03
Oops哎呀.
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糟了
06:05
(Laughter笑声)
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(笑声)
06:08
Here's这里的 another另一个 really bad one.
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这儿还有一个
06:10
JohnEdwardsJohnEdwards.comCOM
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JohnEdwards.com
06:12
(Text文本: Damn该死的 liberal自由主义的)
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(该死的自由主义者)
06:15
(Laughter笑声)
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(笑声)
06:17
So we keep on insulting侮辱 people left and right everyday每天.
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我们就这么每天不停地羞辱别人
06:20
Now, of course课程, we're not just insulting侮辱 people.
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当然 不仅是人
06:22
See here's这里的 the thing, since以来 we're presenting呈现 two randomly随机 chosen选择 words,
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其他东西也难逃厄运 因为我们是随机选取的单词
06:25
interesting有趣 things can happen发生.
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就有了很有趣的结果
06:27
So this actually其实 has given特定 rise上升
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这个正在成为
06:29
to a really big Internet互联网 meme米姆
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互联网上一个流行趋势
06:32
that tens of thousands数千 of people have participated参加 in,
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无数的人参与这个
06:34
which哪一个 is called CAPTCHACAPTCHA art艺术.
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所谓的验证码艺术
06:36
I'm sure some of you have heard听说 about it.
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肯定有人听说过
06:38
Here's这里的 how it works作品.
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是这样
06:40
Imagine想像 you're using运用 the Internet互联网 and you see a CAPTCHACAPTCHA
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假设你在上网看到一个验证码
06:42
that you think is somewhat有些 peculiar奇特,
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你觉得很特别
06:44
like this CAPTCHACAPTCHA. (Text文本: invisible无形 toaster烤面包机)
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比如这个 (隐形的烤面包机)
06:46
Then what you're supposed应该 to do is you take a screen屏幕 shot射击 of it.
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你要做的就是截图
06:48
Then of course课程, you fill out the CAPTCHACAPTCHA
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然后当然就是输入验证码
06:50
because you help us digitize数字化 a book.
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因为你在帮我们电子化书籍
06:52
But then, first you take a screen屏幕 shot射击,
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接下来 你截了图
06:54
and then you draw something that is related有关 to it.
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就画出与它相关的图像
06:56
(Laughter笑声)
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(笑声)
06:58
That's how it works作品.
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就是这样
07:01
There are tens of thousands数千 of these.
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这样作品大概有一万个
07:04
Some of them are very cute可爱. (Text文本: clenched握紧 it)
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有些很可爱 (握紧它)
07:06
(Laughter笑声)
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(笑声)
07:08
Some of them are funnier有趣.
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有些很好玩
07:10
(Text文本: stoned砸死 founders创始人)
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(大醉的创始人)
07:13
(Laughter笑声)
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(笑声)
07:16
And some of them,
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还有一些
07:18
like paleontological古生物 shvisleshvisle,
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比如 “古生物学的史维凿”
07:21
they contain包含 Snoop史努比 Dogg狗狗.
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说不定那儿有史诺谱・道格(美国说唱歌手)
07:23
(Laughter笑声)
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(笑声)
07:26
Okay, so this is my favorite喜爱 number of reCAPTCHA验证码.
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这是我最喜欢的reCAPTCHA数字
07:28
So this is the favorite喜爱 thing that I like about this whole整个 project项目.
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这是我最喜欢的这个项目的部分
07:31
This is the number of distinct不同 people
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这个数字是
07:33
that have helped帮助 us digitize数字化 at least最小 one word out of a book through通过 reCAPTCHA验证码:
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通过reCAPTCHA帮助我们电子化书籍中单词的人数
07:36
750 million百万,
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7.5亿
07:38
which哪一个 is a little over 10 percent百分 of the world's世界 population人口,
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多于世界总人口的十分之一的人们
07:40
has helped帮助 us digitize数字化 human人的 knowledge知识.
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帮助我们电子化人类的知识
07:42
And it is numbers数字 like these that motivate刺激 my research研究 agenda议程.
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正是这样的数字激励我的研究进程
07:45
So the question that motivates能够激励 my research研究 is the following以下:
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那激励我研究进程的问题如下:
07:48
If you look at humanity's人类的 large-scale大规模 achievements成就,
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试想人类的大型成就
07:50
these really big things
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人类共同
07:52
that humanity人性 has gotten得到 together一起 and doneDONE historically历史 --
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创造的那些大型历史性事物-
07:55
like for example, building建造 the pyramids金字塔 of Egypt埃及
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比如 建造埃及金字塔
07:57
or the Panama巴拿马 Canal运河
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开凿巴拿马运河
07:59
or putting a man on the Moon月亮 --
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或者把人类送上月球-
08:01
there is a curious好奇 fact事实 about them,
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这些工程都有个奇怪的事实
08:03
and it is that they were all doneDONE with about the same相同 number off people.
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就是它们基本都是由一样数量的人们完成的
08:05
It's weird奇怪的; they were all doneDONE with about 100,000 people.
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这很奇怪 这些工程都是由大概十万人完成
08:08
And the reason原因 for that is because, before the Internet互联网,
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因为在互联网出现之前
08:11
coordinating协调 more than 100,000 people,
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整合十万人
08:13
let alone单独 paying付款 them, was essentially实质上 impossible不可能.
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这十万人的巨大酬劳基本上是无法支付的
08:16
But now with the Internet互联网, I've just shown显示 you a project项目
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但是有了互联网 刚刚展示的这个项目
08:18
where we've我们已经 gotten得到 750 million百万 people
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就找到了7.5亿人
08:20
to help us digitize数字化 human人的 knowledge知识.
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来帮助我们电子化人类知识
08:22
So the question that motivates能够激励 my research研究 is,
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那么 激励我的研究的问题就是
08:24
if we can put a man on the Moon月亮 with 100,000,
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如果十万人能把一个人送上月球
08:27
what can we do with 100 million百万?
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一亿人能做到什么呢?
08:29
So based基于 on this question,
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基于这个问题
08:31
we've我们已经 had a lot of different不同 projects项目 that we've我们已经 been working加工 on.
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我们有很多项目在进行中
08:33
Let me tell you about one that I'm most excited兴奋 about.
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下面介绍一个最令我兴奋的项目
08:36
This is something that we've我们已经 been semi-quietly半悄然 working加工 on
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这是过去一年半里
08:38
for the last year and a half or so.
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我们低调进行的一个项目
08:40
It hasn't有没有 yet然而 been launched推出. It's called Duolingo听歌.
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还没有真正投入使用 它叫做Duolingo
08:42
Since以来 it hasn't有没有 been launched推出, shhhhhshhhhh!
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因为我们还没有投入使用 嘘!
08:44
(Laughter笑声)
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(笑声)
08:46
Yeah, I can trust相信 you'll你会 do that.
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我相信你们都会保密的
08:48
So this is the project项目. Here's这里的 how it started开始.
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这个项目是这样开始的
08:50
It started开始 with me posing冒充 a question to my graduate毕业 student学生,
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它始于我向我的一名研究生提的问题
08:52
Severin塞韦林 Hacker黑客.
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塞韦林・骇客
08:54
Okay, that's Severin塞韦林 Hacker黑客.
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这就是他
08:56
So I posed构成 the question to my graduate毕业 student学生.
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我向他提了一个问题
08:58
By the way, you did hear me correctly正确地;
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另外你确实没听错
09:00
his last name名称 is Hacker黑客.
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他姓骇客
09:02
So I posed构成 this question to him:
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我向他提了个问题:
09:04
How can we get 100 million百万 people
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怎么才能找到一亿人
09:06
translating翻译 the Web卷筒纸 into every一切 major重大的 language语言 for free自由?
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把互联网上的内容免费翻译成所有的主要语言?
09:09
Okay, so there's a lot of things to say about this question.
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这个问题有好几个方面
09:11
First of all, translating翻译 the Web卷筒纸.
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首先是翻译网页
09:13
So right now the Web卷筒纸 is partitioned分区 into multiple languages语言.
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现在的网页内容主要分为几大语言
09:16
A large fraction分数 of it is in English英语.
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其中一个大的分支是英语
09:18
If you don't know any English英语, you can't access访问 it.
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如果你不会英语就无法使用
09:20
But there's large fractions馏分 in other different不同 languages语言,
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但是还有其他几种不同的语言
09:22
and if you don't know those languages语言, you can't access访问 it.
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如果你不会那几种也无法使用
09:25
So I would like to translate翻译 all of the Web卷筒纸, or at least最小 most of the Web卷筒纸,
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我打算把所有网页 大部分网页
09:28
into every一切 major重大的 language语言.
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翻译成主要语言
09:30
So that's what I would like to do.
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这是我想做的
09:32
Now some of you may可能 say, why can't we use computers电脑 to translate翻译?
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也许有人会说 怎么不用电脑翻译?
09:35
Why can't we use machine translation翻译?
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为什么我们不用机器翻译?
09:37
Machine translation翻译 nowadays如今 is starting开始 to translate翻译 some sentences句子 here and there.
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机器翻译已经在应用中
09:39
Why can't we use it to translate翻译 the whole整个 Web卷筒纸?
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为什么不用它来翻译所有网页呢?
09:41
Well the problem问题 with that is that it's not yet然而 good enough足够
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问题就是机器翻译还不够好
09:43
and it probably大概 won't惯于 be for the next下一个 15 to 20 years年份.
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也许将来的15到20年内都不行
09:45
It makes品牌 a lot of mistakes错误.
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机器翻译有很多错误
09:47
Even when it doesn't make a mistake错误,
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甚至就算它翻对的时候
09:49
since以来 it makes品牌 so many许多 mistakes错误, you don't know whether是否 to trust相信 it or not.
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因为它的错误率太高 你也不敢相信它
09:52
So let me show显示 you an example
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比如这个例子
09:54
of something that was translated翻译 with a machine.
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是由机器翻译的
09:56
Actually其实 it was a forum论坛 post岗位.
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这是个论坛帖子
09:58
It was somebody who was trying to ask a question about JavaScriptJavaScript的.
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有人提了关于Java语言的一个问题
10:01
It was translated翻译 from Japanese日本 into English英语.
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是从日语翻译成英语
10:04
So I'll just let you read.
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你可以读一下
10:06
This person starts启动 apologizing道歉
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他首先道歉
10:08
for the fact事实 that it's translated翻译 with a computer电脑.
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这是机器翻译的内容
10:10
So the next下一个 sentence句子 is is going to be the preamble前言 to the question.
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下一个句子开始涉及问题
10:13
So he's just explaining说明 something.
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他开始说明
10:15
Remember记得, it's a question about JavaScriptJavaScript的.
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记住 这个问题是关于Java语言的
10:19
(Text文本: At often经常, the goat-time山羊时间 install安装 a error错误 is vomit呕吐.)
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(文字:常常,山羊时间启动错误被吐出来)
10:23
(Laughter笑声)
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(笑声)
10:27
Then comes the first part部分 of the question.
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接下来是问题的第一部分
10:30
(Text文本: How many许多 times like the wind, a pole, and the dragon?)
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(文字:有多少次像风,像杆子,像龙?)
10:34
(Laughter笑声)
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(笑声)
10:36
Then comes my favorite喜爱 part部分 of the question.
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接下来是最好玩的部分
10:39
(Text文本: This insult侮辱 to father's父亲的 stones石头?)
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(文字:这是对父亲的石头的侮辱?)
10:42
(Laughter笑声)
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(笑声)
10:44
And then comes the ending结尾, which哪一个 is my favorite喜爱 part部分 of the whole整个 thing.
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接下来是结尾 我最喜欢的部分
10:47
(Text文本: Please apologize道歉 for your stupidity糊涂事. There are a many许多 thank you.)
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(文字:请为你的愚蠢道歉,很多谢谢)
10:51
(Laughter笑声)
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(笑声)
10:53
Okay, so computer电脑 translation翻译, not yet然而 good enough足够.
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可见 机器翻译 还不够好
10:55
So back to the question.
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回到问题上去
10:57
So we need people to translate翻译 the whole整个 Web卷筒纸.
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我们需要人来翻译所有网页
11:00
So now the next下一个 question you may可能 have is,
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下一个问题是
11:02
well why can't we just pay工资 people to do this?
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为什么不付钱找人做呢?
11:04
We could pay工资 professional专业的 language语言 translators译者 to translate翻译 the whole整个 Web卷筒纸.
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我们可以找专业翻译人员来翻译整个网页
11:07
We could do that.
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可以这么做
11:09
Unfortunately不幸, it would be extremely非常 expensive昂贵.
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但是 这会无比昂贵
11:11
For example, translating翻译 a tiny, tiny fraction分数 of the whole整个 Web卷筒纸, Wikipedia维基百科,
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比如 翻译互联网很小很小的一个部分 维基百科
11:14
into one other language语言, Spanish西班牙语.
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英语翻译成西班牙语
11:17
Wikipedia维基百科 exists存在 in Spanish西班牙语,
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维基百科有西班牙语
11:19
but it's very small compared相比 to the size尺寸 of English英语.
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但是相比英语部分小多了
11:21
It's about 20 percent百分 of the size尺寸 of English英语.
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大概是英语内容的百分之二十
11:23
If we wanted to translate翻译 the other 80 percent百分 into Spanish西班牙语,
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如果我们把剩下的百分之八十翻译成英语
11:26
it would cost成本 at least最小 50 million百万 dollars美元 --
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就得至少五千万美元-
11:28
and this is at even the most exploited利用, outsourcing外包 country国家 out there.
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这还是在最便宜的服务外包国家
11:31
So it would be very expensive昂贵.
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所以这个方法很昂贵
11:33
So what we want to do is we want to get 100 million百万 people
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我们要的是一亿人
11:35
translating翻译 the Web卷筒纸 into every一切 major重大的 language语言
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免费把网页内容翻译成
11:37
for free自由.
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所有主要语言
11:39
Now if this is what you want to do,
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如果你要这么做的话
11:41
you pretty漂亮 quickly很快 realize实现 you're going to run into two pretty漂亮 big hurdles障碍,
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就会意识到面临两个非常
11:43
two big obstacles障碍.
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巨大的障碍
11:45
The first one is a lack缺乏 of bilinguals双语.
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首先是缺乏掌握双语的人
11:48
So I don't even know
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我甚至不知道
11:50
if there exists存在 100 million百万 people out there using运用 the Web卷筒纸
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是否有一亿个互联网使用者
11:53
who are bilingual双语 enough足够 to help us translate翻译.
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掌握双语来进行翻译
11:55
That's a big problem问题.
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这是个大问题
11:57
The other problem问题 you're going to run into is a lack缺乏 of motivation动机.
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另一个问题是缺少鼓励机制
11:59
How are we going to motivate刺激 people
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怎么才能让人们
12:01
to actually其实 translate翻译 the Web卷筒纸 for free自由?
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甘愿免费翻译网页?
12:03
Normally一般, you have to pay工资 people to do this.
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通常你得付钱请人干活儿
12:06
So how are we going to motivate刺激 them to do it for free自由?
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那么怎么才能让他们无偿劳动呢?
12:08
Now when we were starting开始 to think about this, we were blocked受阻 by these two things.
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当我们着手考虑这个项目的时候这是拦在面前的两大问题
12:11
But then we realized实现, there's actually其实 a way
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后来我们意识到
12:13
to solve解决 both these problems问题 with the same相同 solution.
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有一个方法可以一举解决这两个问题
12:15
There's a way to kill two birds鸟类 with one stone.
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一箭双雕
12:17
And that is to transform转变 language语言 translation翻译
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这就是把翻译转化成
12:20
into something that millions百万 of people want to do,
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无数人想做的事情
12:23
and that also helps帮助 with the problem问题 of lack缺乏 of bilinguals双语,
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同时解决双语人员人手不够的问题
12:26
and that is language语言 education教育.
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这就是语言学习
12:29
So it turns out that today今天,
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当今
12:31
there are over 1.2 billion十亿 people learning学习 a foreign国外 language语言.
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有超过12亿人口在学习外语
12:34
People really, really want to learn学习 a foreign国外 language语言.
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人们迫切得想学习外语
12:36
And it's not just because they're being存在 forced被迫 to do so in school学校.
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而且这不是学校里不得不做的功课
12:39
For example, in the United联合的 States状态 alone单独,
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比如在美国
12:41
there are over five million百万 people who have paid支付 over $500
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有超过五百万的人在为外语学习软件
12:43
for software软件 to learn学习 a new language语言.
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每人支付超过五百美元
12:45
So people really, really want to learn学习 a new language语言.
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所有人们非常想学外语
12:47
So what we've我们已经 been working加工 on for the last year and a half is a new website网站 --
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过去一年半里我们建立的新网站
12:50
it's called Duolingo听歌 --
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叫做Duolingo-
12:52
where the basic基本 idea理念 is people learn学习 a new language语言 for free自由
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就是基于这个让人们免费学习外语
12:55
while simultaneously同时 translating翻译 the Web卷筒纸.
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同时翻译网页的想法
12:57
And so basically基本上 they're learning学习 by doing.
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就是让他们学以致用
12:59
So the way this works作品
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使用方法是这样
13:01
is whenever每当 you're a just a beginner初学者, we give you very, very simple简单 sentences句子.
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如果你是个新手 我们会给出非常非常简单的句子
13:04
There's, of course课程, a lot of very simple简单 sentences句子 on the Web卷筒纸.
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网页上有很多简单的句子
13:06
We give you very, very simple简单 sentences句子
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我们给出非常简单的句子
13:08
along沿 with what each word means手段.
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以及句中单词释义
13:10
And as you translate翻译 them, and as you see how other people translate翻译 them,
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然后你翻译一下 并且可以看到别人是如何翻译的
13:13
you start开始 learning学习 the language语言.
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这样学习外语
13:15
And as you get more and more advanced高级,
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当你级别提高后
13:17
we give you more and more complex复杂 sentences句子 to translate翻译.
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我们会给出越来越复杂的句子让你翻译
13:19
But at all times, you're learning学习 by doing.
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这整个过程 你都是边学边用
13:21
Now the crazy thing about this method方法
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这个方法令人疯狂之处
13:23
is that it actually其实 really works作品.
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是它居然确实有效
13:25
First of all, people are really, really learning学习 a language语言.
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首先 人们可以通过它学外语
13:27
We're mostly大多 doneDONE building建造 it, and now we're testing测试 it.
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我们建完了网站,它现正在测试中
13:29
People really can learn学习 a language语言 with it.
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人们可以用它学习外语
13:31
And they learn学习 it about as well as the leading领导 language语言 learning学习 software软件.
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完全可以跟外语学习软件媲美
13:34
So people really do learn学习 a language语言.
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所以用它确实可以学外语
13:36
And not only do they learn学习 it as well,
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不仅可以学好
13:38
but actually其实 it's way more interesting有趣.
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而且更有趣味性
13:40
Because you see with Duolingo听歌, people are actually其实 learning学习 with real真实 content内容.
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因为通过Duolingo人们学的是真正的语言使用内容
13:43
As opposed反对 to learning学习 with made-up捏造 sentences句子,
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而不是编造的句子
13:45
people are learning学习 with real真实 content内容, which哪一个 is inherently本质 interesting有趣.
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通过学习真正的文本内容,趣味性大大提高
13:48
So people really do learn学习 a language语言.
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这样人们就实实在在学习外语
13:50
But perhaps也许 more surprisingly出奇,
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最令人惊讶的是
13:52
the translations译文 that we get from people using运用 the site现场,
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网站使用者的翻译
13:55
even though虽然 they're just beginners初学者,
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甚至是初学者的翻译
13:57
the translations译文 that we get are as accurate准确 as those of professional专业的 language语言 translators译者,
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和专业的翻译人员几乎不相上下
14:00
which哪一个 is very surprising奇怪.
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这很让人惊讶
14:02
So let me show显示 you one example.
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让我给你们看一个例子
14:04
This is a sentence句子 that was translated翻译 from German德语 into English英语.
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这是一个从德语翻译成英语的例子
14:06
The top最佳 is the German德语.
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上面是德语
14:08
The middle中间 is an English英语 translation翻译
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中间是一名专业英语翻译人员
14:10
that was doneDONE by somebody who was a professional专业的 English英语 translator翻译者
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翻译的句子
14:12
who we paid支付 20 cents a word for this translation翻译.
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一个词二十美分的价钱
14:14
And the bottom底部 is a translation翻译 by users用户 of Duolingo听歌,
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下面是Duolingo使用者的翻译
14:17
none没有 of whom knew知道 any German德语
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他们在使用该网站前
14:19
before they started开始 using运用 the site现场.
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不会任何德语
14:21
You can see, it's pretty漂亮 much perfect完善.
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可以看到 几乎很完美
14:23
Now of course课程, we play a trick here
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当然 为了让翻译达到专业水准
14:25
to make the translations译文 as good as professional专业的 language语言 translators译者.
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我们也想了个办法
14:27
We combine结合 the translations译文 of multiple beginners初学者
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我们把多名翻译者的翻译结合起来
14:30
to get the quality质量 of a single professional专业的 translator翻译者.
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得到专业人员的水准
14:33
Now even though虽然 we're combining结合 the translations译文,
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即使我们要结合翻译
14:38
the site现场 actually其实 can translate翻译 pretty漂亮 fast快速.
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这个网站仍然可以迅速翻译
14:40
So let me show显示 you,
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让我展示一下
14:42
this is our estimates估计 of how fast快速 we could translate翻译 Wikipedia维基百科
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这是我们对维基百科翻译工程的预计
14:44
from English英语 into Spanish西班牙语.
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从英语翻译成西班牙语
14:46
Remember记得, this is 50 million百万 dollars-worth美元价值 of value.
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要记住 这可是价值五千万美元的工程
14:49
So if we wanted to translate翻译 Wikipedia维基百科 into Spanish西班牙语,
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如果要把维基百科从英文翻译成西班牙语
14:51
we could do it in five weeks with 100,000 active活性 users用户.
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十万名活跃用户可以在五周内完成
14:54
And we could do it in about 80 hours小时 with a million百万 active活性 users用户.
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一百万活跃用户可以在八十小时内完成
14:57
Since以来 all the projects项目 that my group has worked工作 on so far have gotten得到 millions百万 of users用户,
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现在我们的项目小组已经有了上百万使用者
15:00
we're hopeful有希望 that we'll be able能够 to translate翻译
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我们希望可以以极快的速度
15:02
extremely非常 fast快速 with this project项目.
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进行这个翻译工程
15:04
Now the thing that I'm most excited兴奋 about with Duolingo听歌
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现在我对Duolingo最兴奋的就是
15:07
is I think this provides提供 a fair公平 business商业 model模型 for language语言 education教育.
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它为外语教育创造了一个公平的商业模式
15:10
So here's这里的 the thing:
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是这样:
15:12
The current当前 business商业 model模型 for language语言 education教育
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目前外语教育的商业模式是
15:14
is the student学生 pays支付,
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学生付钱
15:16
and in particular特定, the student学生 pays支付 Rosetta罗塞塔 Stone 500 dollars美元.
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主要就是学生购买罗赛塔石碑五百美元的软件
15:18
(Laughter笑声)
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(笑声)
15:20
That's the current当前 business商业 model模型.
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这是目前的商业模式
15:22
The problem问题 with this business商业 model模型
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这个模式的问题是
15:24
is that 95 percent百分 of the world's世界 population人口 doesn't have 500 dollars美元.
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世界人口的百分之九十五没有五百美元
15:27
So it's extremely非常 unfair不公平 towards the poor较差的.
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所以这个模式对穷人极度不公平
15:30
This is totally完全 biased towards the rich丰富.
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这是个面向富人的模式
15:32
Now see, in Duolingo听歌,
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而Duolingo
15:34
because while you learn学习
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因为你学习的时候
15:36
you're actually其实 creating创建 value, you're translating翻译 stuff东东 --
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也创造价值,你在翻译东西-
15:39
which哪一个 for example, we could charge收费 somebody for translations译文.
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因为比如我们得付钱给人翻译东西
15:42
So this is how we could monetize赚钱 this.
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这样你的学习过程就货币化了
15:44
Since以来 people are creating创建 value while they're learning学习,
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因为人们学习的时候同时创造价值
15:46
they don't have to pay工资 their money, they pay工资 with their time.
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他们就不用付钱 而是付出时间
15:49
But the magical神奇 thing here is that they're paying付款 with their time,
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最妙的是 虽然人们得付出时间
15:52
but that is time that would have had to have been spent花费 anyways无论如何
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但这个时间是他们学习外语无论如何
15:54
learning学习 the language语言.
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都会付出的那部分时间
15:56
So the nice不错 thing about Duolingo听歌 is I think it provides提供 a fair公平 business商业 model模型 --
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所以Duolingo做的好事就是提供了一个公平的商业模式-
15:59
one that doesn't discriminate辨析 against反对 poor较差的 people.
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这个模式对穷人一样敞开机会
16:01
So here's这里的 the site现场. Thank you.
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这就是这个网站 谢谢
16:03
(Applause掌声)
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(掌声)
16:11
So here's这里的 the site现场.
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这个网站
16:13
We haven't没有 yet然而 launched推出,
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我们还没有投入应用
16:15
but if you go there, you can sign标志 up to be part部分 of our private私人的 beta公测,
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但是如果你去我们的页面的话可以注册
16:18
which哪一个 is probably大概 going to start开始 in about three or four weeks.
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也许三四周后就可以开始了
16:20
We haven't没有 yet然而 launched推出 this Duolingo听歌.
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我们还没有投入使用Duolingo
16:22
By the way, I'm the one talking here,
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另外 虽然是我在这里介绍Duolingo
16:24
but actually其实 Duolingo听歌 is the work of a really awesome真棒 team球队, some of whom are here.
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但这个网站是一个优秀的团队的成果 这是其中一些人
16:27
So thank you.
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谢谢你们
16:29
(Applause掌声)
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(掌声)
Translated by Chunxiang Qian
Reviewed by Angelia King

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ABOUT THE SPEAKER
Luis von Ahn - Computer scientist
Luis von Ahn builds systems that combine humans and computers to solve large-scale problems that neither can solve alone.

Why you should listen

Louis von Ahn is an associate professor of Computer Science at Carnegie Mellon University, and he's at the forefront of the crowdsourcing craze. His work takes advantage of the evergrowing Web-connected population to acheive collaboration in unprecedented numbers. His projects aim to leverage the crowd for human good. His company reCAPTCHA, sold to Google in 2009, digitizes human knowledge (books), one word at a time. His new project is Duolingo, which aims to get 100 million people translating the Web in every major language.

More profile about the speaker
Luis von Ahn | Speaker | TED.com